Practice-based research networks (PBRNs) are organizations of clinicians working in practices that engage in research. PBRNs have emerged as a vital lynchpin in efforts to translate research into practice by translating practice into research. However, the development and maintenance and the continued engagement of busy community practices in cancer research requires specialized expertise and ongoing support. Therefore, the mission of the PBRN Core Facility is: To develop and sustain practice-based research networks that engage in cancer research; To advise and assist Case Comprehensive Cancer Center (Case CCC) investigators in developing community-based cancer research studies for implementation in PBRNs; To provide infrastructure that supports the implementation of Case CCC investigators' research studies in PBRNs, and that supports network practice-initiated research. The Practice-Based Research Network Core Facility supports the engagement of patients, clinicians, practices, and health systems in cancer research by: 1. Starting new PBRNs; 2. Developing the infrastructure of existing PBRNs; 3. Providing PBRN methods consultations to Cancer Center investigators and participating practices; 4. Advising and assisting investigators on research project implementation in PBRNs. The PBRN Core has started and sustained 8 successful PBRNs and is developing 5 new PBRNs. The established PBRNs represent major healthcare systems and include family medicine practices, federallyqualified health centers, community oncology practices, pediatrics practices, and general dentistry practices. The PBRN Core has facilitated the development and implementation of 23 funded research projects within the PBRNs that it has developed and sustained. Fourteen of these projects have been funded by NCI, and 6 supported by ACS. Grant funding for these projects totals over $15 million. The demand for the PBRN Core's services is strong and growing, and the potential for continued and expanded use of the facility is excellent. At present, 19 members of the Case CCC are pursuing 15 different lines of inquiry likely to result in funded studies to be implemented in Core-supported PBRNs.